Automatic valve attachment for power mechanisms



2 Sheets--Sheet 1.

- (No Model.)

S. N. KNIGHT.

AUTOMATIC VALVE ATTAGHMENT FOR POWER MECHANISMS.

Patented May 28, 1889.

N. PETERS. Pho

(No Model.) 2 Sheets--Sheet 2.

S. N. KNIGHT.

AUTOMATIC VALVE ATTAGHMENT FOR POWER MEGHANISMS.

No. 404,202. Patented May 28, 1889.

UNITED STATES PATENT OFFICE.

SAMUEL N. KNIGHT, O1 SUTTER CREEK, CALIFORNIA AUTOMATIC VALVE ATTACHMENT FOR POWER MECHANISMS.

SPECIFICATION forming part of Letters Patent No. 404,202, dated May 28, 1889.

Application filed November 3, 1888. Serial No. 289,911. (No model.)

' I To aZZ whom it may concern:

Be it known that I, SAMUEL N. KNIGHT, of Sutter Creek, Amador county, State of California, have invented an Improvement in Automatic Valve Attachments for Power Mechanism; and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to an automatic mechanism whereby a power-producing engine or water-wheel is stopped or started by variations in the pressure of the air which it is used to compress.

It consists of a valve controlling the'wheel or engine, pistons of different diameter secured to the stem of the valve, so that by the varying pressures upon one or'the other of the pistons the Valve may be opened or closed.

It further consists of certain details of construction, to be hereinafter more fully described.

Referring to the accompanying drawings for a more complete explanation of my invention, Figure l is a general view of an apparatus showing my invention. Fig. 2 is a vertical section taken through the cylinders and pistons, and showing the valve actuated thereby and the supply and exhaust passages. I

My invention is applicable to any form of motor which drives air-compressors, the increase or decrease of the air-pressure serving to stop or start the engine through the medium of an unequal pressure upon pistons of different diameters, and a valve actuated by said pistons. shown my invention applied to air-compressors which are driven by momentum waterwheels, and the regulation is effected by the variation in the pressure of the air from the compressor, which acts directly upon a piston moving within a cylinder, which piston is counterbalanced by a smaller piston fixed to the same rod and subject to a counterpressure of water under a high head or other medium. The stem or rod to which these pistons are secured connects directly with the valve which controls the passages supplying water to move the piston by which the water-wheel gate is opened and closed, thus making the supply of water regulate itself.

In the present case I have This device is especially applicable to wheels which are driven by the momentum of a stream of water under a heavy pressure, and in which the gate supplying the said stream is actuated by a piston moving within the cylinder, this class of gates being well illustrated in my patent, No. 267,087, November 7 1882. In my present invention I have shown a general view of the water-wheel, its gate, the cylinder, and piston by which the gate is opened and closed, and the air compressor and receiver, it being only necessary to state that the water supplied by the valve in my present invention is led to opposite ends of the gate-controlling cylinder, so as to move the piston to either open or close the gate, as may be required.

A is a valve, which may be either a balance-valve, as shown in the present drawings, or it may be in the form of an ordinary D- valve, these valves in either case controlling the supply-ports B and O and the exhaustport E. The valve A is fixed to a valve-stem, F, which extends upwardly from the valvechamber into and through two cylinders, G and II, of different diameters, but forming a continuation of each other and about the same axis. The lower cylinder, G, is of smaller diameter than the upper one, H, and has a piston, I, secured to the stem or rod F, so as to fit within the cylinder. The upper cylinder, of larger diameter, has a piston, J, similarly fitted into it and upon the same rod, F. The lower 7. cylinder has a supply-pipe, K, opening into it, which supplies water from a source which produces a heavy pressure, equal, usually, to from two to four hundred feet of elevation. A branch of this same pipe opens into the chamber at the lower end of the valve A, as shown at L, and as the pressure within the cylinder acts upon the top of the valve passing down around the valve-stem the pressure through the pipe L counterbalances it by acting equally upon the bottom of the valve, so that the movement of the valve is easily produced by the varying action of the two pistons. The upper piston,J, is made of considerably larger diameter than the piston I and fits in the correspondingly-larger cylinder 11. Air is supplied through apassage, M, from the reservoir to press upon the top of this piston. This air-supply is derived directly from the air-compressor or the pipe or reservoir connected therewith.

The relative size of the two pistons I and J and their cylinders will depend upon the pressure of water available and the pressure of air desired. It, for instance, an air-pressure of one hundred or one hundred and ten feet is desired, while the water-pressure is equal to four or five or six hundred feet of elevation, it will be easy to calculate the relative area of the two pistons and to make them properlyproportional to each other. per end 01' the piston-rod 1 after passing out through a stutting-box, which makes a tight joint, has upon it a receptacle into which weights may be put to counterbalance the water-pressure in case it is desired to employ a less pressure of air than had been determined upon in constructing the machine. The lower end of said piston-rod and valvestem F, after passing through a stufiing-box, N, at the bottom of the valve-chamber, is fitted to rest upon the short arm of a lever, O, the long arm of which may have weights applied to it so as to assist the pressure of the water upon the lower piston, and this will increase the pressure of air within the receiver and also the pressure which will be necessary to move the pistons downward so as to open the valve. -l-y means of this weighted lever at the bottom and the weight- .receptacle above it will be easy to vary the air-pressu re at any time to suit convenience or circumstances.

The operation of the device will be as follows: The pressure which it is desired to maintain upon the compressor or reservoir having been determined, the relative sizes of the cylinders and the weights, acting upon the upper and lower end of the piston-rodand valve-stein, are adjusted to correspond. The air-con'ipressor is driven by power derived from the water-whecl, as shown. When the pressure of air in the reservoir has reached its maximum, any increase will act upon the upper piston, .l, and, overcoming the pressure of the water upon the lower piston, I, in the small cylinder, both pistons and the valvestem will be forced down until the upper end of the val ve A exposes the passage 1-3, through which water will then flow to the cylinder 1 and move the piston within it, so as to close the water-gate and stop the wateravhcel. As soon as the fit-pressure becomes reduced below the desired point, the water-pressure in the lower cylinder, (4, acting upon ihe piston I, will overcmne the g n'essure upon the piston The up J and will. move the two pistons upward, car rying with them the valve A until the lower passage, (3, to the cylinder P is opened, and the water will pass through this passage to the opposite end of the gate-controlling cylinder, thus moving the piston in the opposite direction and opening the gate. It will be seen that when either of the passages B or (J is opened to supply water to the gate-coi'itrolling cylinder 1? the other passage will be in communication with the exhaust-passage E, so that water may escape from the opposite end of the cylinder 1.

By this construction I am enabled to automatically control and regulate the waterpressure to any desired degree.

It will be manifest that the supply-valve of an engine which might be used to drive the compressor could be controlled in the same manner with little or no mechanical. change of parts.

This device is entirely automatic and will operate day and night continuously for a long period without attention.

Having thus described my inventitm, what I claim as new, and desire to secure by Letters Patent, is

1. The valve-chamber having the supply and exhaust passages 13, and E, and the valve A, in combination with the pistons of different diameters moving in COPI'GSPOlHllll cylinders, the water and air supply passages opening into the said cylinders upon opposite sides of the two pistons, substantially as and for the purpose herein described.

2. The cylinders G- and II, having the pistons I and .l fitted therein, a pipe supplying water or other medium under pressure beneath the lower piston, and a pipe supplyin air under pressure above the upper piston, a valve connected with the common piston-rod of the two pistons, and supply and exhaust passages controlled by said valve, in combination with an air-compressorconnected with the upper cylinder, and a motor from. which power is derived to operate said compressor, the gate of said motor being moved by a piston fitting into a cylinder, to the opposite ends of which. the supply-passages from the valve A connnunicate, substantially as herein described.

In witness whereof I havchereunto set my hand.

SAMUEL N. KNIGII'I. 

